The
2005 spring harvest of pink shrimp off North Carolina is likely to
again lag behind average harvests over the past four decades, according
to National Oceanic and Atmospheric Administration scientists at the
agency’s Beaufort, N.C., laboratory. The scientists base their
projection primarily on colder than usual water temperatures along
the North Carolina coast.

Pink
shrimp account for about one-quarter of the state’s total annual
shrimp harvest, which since the early 1960s has averaged about 985,000
pounds. Brown shrimp, caught later in the year, comprise most of the
balance of the total shrimp harvest.

NOAA
scientists, representing the agency’s National Ocean Service
and National Fisheries Service, say the projected shortfall is based
on a two-week low winter temperature of 42.3°F in waters off Beaufort,
N.C. That temperature contrasts with an average 44.1°F low averaged
over the past four decades.

Winter
water temperatures along the North Carolina coast are especially important
because pink shrimp use the estuaries as nursery grounds. With unusually
cool winter water temperatures, shrimps are unable to adapt to changing
salinities, increasing mortality.

In
five of the past six years, abnormally low minimum winter water temperatures
in North Carolina estuaries have led to sub-normal harvests the following
spring. Pink shrimp off North Carolina are at the northern limits
of their temperature tolerance and are therefore particularly sensitive
to temperature variations. Average annual harvests of about 985,000
pounds contrast with pink shrimp harvests of 219,000 pounds and 135,000
pounds in the cold winter years, 2003 and 2004, respectively.

NOAA
scientists point out that economic and environmental factors in addition
to cold water temperatures – for instance, a previous year’s
shrimp mortality resulting from harvesting or by-catch – can
influence spring pink shrimp populations available to be caught. Reduced
fishing efforts resulting from depressed market prices and environmental
impediments to fishing can also lead to lower harvests, making precision
forecasts extremely difficult.

The
forecasts, based on an “ecological forecasting” capability
developed by the NOAA scientists, have proven reliable in recent years.

"These
type of forecasts are invaluable in helping commercial fishermen make
better economic decisions about alternative fishing areas or possible
alternative fish and shellfish to target," said Jerry Schill,
president of the North Carolina Fisheries Association. "It shows
that once fishermen find that the science is credible, they'll accept
and use it."

“Ecological
forecasts are part of a growing suite of new tools helping us to use
science to gain value for the public,” said Richard
W. Spinrad, assistant administrator of NOAA’s National Ocean
Service. “They add value to scientific information that can
help guide decisions concerning the use of coastal and ocean resources.
The pink shrimp forecast is one application of this technology.”

“This new forecasting technology will aid fisheries managers
as they work to develop ecosystem management approaches for mid-Atlantic
fisheries.”said William
T. Hogarth, assistant administrator of NOAA Fisheries Service.
“It’s part of the NOAA to effort to protect our ocean
resources.”

In
recent years, other extended periods of cold winters, as in the six
years from 1977 through 1982, were associated with significantly reduced
pink shrimp harvests. Scientists are hoping that further research
can indicate similar impacts on other important fisheries species.
Along with pink shrimp (Farfantepenaeus duorarum), an important fisheries
resource in North Carolina and South Atlantic and Gulf Coast states,
other marine species also have over-wintering juvenile stages sensitive
to low estuary temperatures. NOAA scientists hope to refine their
ecological monitoring techniques for other species, such as the Atlantic
croaker, also sensitive to cooler water temperatures.

NOAA
Fisheries Service is dedicated to protecting and preserving our nation’s
living marine resources and their habitat through scientific research,
management and enforcement. NOAA Fisheries Service provides effective
stewardship of these resources for the benefit of the nation, supporting
coastal communities that depend upon them, and helping to provide
safe and healthy seafood to consumers and recreational opportunities
for the American public.

NOAA,
an agency of the U.S. Department of Commerce, is dedicated to enhancing
economic security and national safety through research to better understand
weather and climate-related events and to manage wisely the nation's
coastal and marine resources.